Making users to use port 587 for submission emails

[Mike Klinke]

On Saturday 10 September 2005 04:48, Sasa Stupar wrote:
> Hi!
>
> I am running Sendmail 8.13.4 on FC4 with cyrus2. I have
> configured sendmail to listen on ports 25 and 587. Since all of
> the client mail software use port 25 by default instead of 587,
> how do I make users to use 587 and deny access to 25? Something
> like: when they try to connect to port 25, they get back error -
> you are not a server so you must use port 587. Any idea?
>
> Regards,
> Sasa

If you don't wish to have other servers connecting to deliver mail 
to this box don't allow port 25 through the firewall and your users 
will get the hint that port 587 is required.  

I assume that you use port 587 for the convenience of those users 
who are roaming through ISP's that have blocked port 25. 

Why would you care if a roaming user connects to port 25 when 
connecting from an ISP that doesn't block port 25?

Regards, Mike Klinke